Jacquard knitting on a circular knitting machine requires needle selection of specific knitting needles being switched between active and inactive positions. Such needle selection is typically provided by jacquard pattern control mechanisms which include pattern selection devices. Such jacquard control mechanisms, including their pattern selection devices, are discussed in co-pending United States patent application, Ser. No. 771,519, now U.S. Pa. No. 5,689,977, commonly owned with this application and incorporated herein by reference.
As is stated in U.S. Pat. No. 5,689,977, prior pattern selection devices combining a permanent magnet and an electromagnet required a plurality of control electromagnets in order to function properly. In addition, such devices were required to limit the size of the electromagnets such that the magnetic attraction generated thereby would not be stronger than that of the permanent magnet. Therefore, both the permanent magnet and the electromagnets had to be quite large which caused spatial problems in the knitting machines.
Applicant solved many of these problems and deficiencies in U.S. Pat. No. 5,689,977 by pattern selection devices embodying both a permanent magnet and an electromagnet working in concert to provide the necessary magnetic attraction while using small magnets. The present invention is an improvement on the invention of U.S. Pat. No. 5,689,977.